Apparatus for keying and locking elements to their retainers

ABSTRACT

This is a system and apparatus for keying and locking tools and like elements such as punches and die and guide buttons in the appropriate bores of their retainers. The system requires the formation of a flat on the head end of the element to be inserted and locked in a retainer bore while the wall of the bore to position opposite the flat is drilled and reamed, in an axial sense, to provide parallel pin holes which open at one side to the bore. Each pin hole receives a dowel type pin which, however, has a flat along one side portion. The flat on the pin is positioned to be exposed to the bore and to generally face the flat on the inserted tool. The dowel pins are specially designed to include a taper which enables a preliminary non-seated positioning of the respective pins in their holes while the related tool is inserted in the associated bore, whereupon each pin is rotatively positioned as required to abut the flat on the inserted tool. The pins are then driven to a seated locking position referenced to the flat on the tool. The use of plural pins, so formed and utilized, eliminates the need for close tolerance in machining the related parts and insures a precise and simple procedure in the locking of a tool or other element in a desired orientation and place.

[11] 3,797,352 14 1 Mar. 19, 1974 [5'41 APPARATUS FOR Knvme AND LOCKINGELEMENTS TO THEIR RETAINERS Robert E. Smith, Kettering, Ohio [73]Assignee: Dayton Progress Corporation, Dayton, Ohio 22 Filed: Jan. 26,1973 21 Appl. No.: 326,582

[75] Inventor:

3,640,170 Bennettuf. 83/698 Primary Examiner-Willie G. AbercrombieAttorney. Agent or Firm lerome P. Bloom [57 ABSTRACT This is a systemand apparatus for keying and locking tools and like elements such aspunches and die and guide buttons in the appropriate bores of theirretainers. The system requires the formation of a flat on the head endof the element to be inserted and locked in aretainer bore while thewall of the bore to position opposite the flat is drilled and reamed, inan axial sense, to provide parallel pin holes which open at one side tothe bore. Each pin hole receives a dowel type pin which, however, has aflat along one side portion.

The flat'on the pin is positioned to be exposed to the bore and togenerally face the flat on the inserted tool. The dowel pins arespecially designed to include a taper which enables a preliminarynon-seated position ing of the respective pins in their holes while therelated tool is inserted in the associated bore, whereupon each pin isrotatively positioned as required to abut theflat on the inserted tool.The pins are then driven to a seated locking position'referenced to theflat on the tool. The use of plural pins, so formed and utiliied,eliminates the need for close tolerance in machining the related partsand insures a precise and simple procedure in the locking of a tool orother element in a desired orientation and place.

12 Claims, 7 Drawing Figures PAIENTEUMAR 19 1974 FIG-6 BACKGROUND OF THEINVENTION.

This invention relates to a new and improved system and apparatus forkeying and locking an element in a precisely required positionreferenced to a retainer. It has particular and significant advantagefor use in the tool and die industry and will be so described though notso limited in application. A most important application is its use tokey and lock in place such items of a die as punches, related guide anddie buttons, and other elements having like function.

While there are many methods utilized for orienting and lockingperforator type tools to their retainer, they all present disadvantagesand problems of serious concern.

One such method is the dowel-slot method. In use of this method a holefor a dowel is machined partially in a tool head, in a sense tangent toits body, and partially in the wall surface of the tool accommodatingbore. The procedure requires pre-drilling,'reaming and jig grinding toextremely close tolerance. Not only is the nature of these operationssuch to substantially increase set up and machiningcosts but in usethereof there is much difficulty found in attempting to achieve a propertit and in maintaining a proper position of the tool. An importantobjection to use of the dowel-slot method is that it inherently makesinterchanging or replacement of a toolextremely difficult. This becomesobvious when one considers the need either to machine a slot inareplacement tool which is highly criticalas to dimension and orientationor to rework the whole retainer-tool :assembly to accommodate adifferent dowel pin. The latter is quiteirnpractical and problems arecompounded when dealing with tools such as headless perforators. v v

Another method of the prior art is the key-flat method. This is mostcommonly used to date and requires that a flat be ground on the head ofa perforator, for example, in a sense tangent to its body. A related keyrequires that an accommodating pocket be milled in the wall of the boreof the retainer which is to receive the perforator. In use of thismethod, if there is any variation in the diametric tolerance of theperforator body, it is reflected in the fit from the center of theperforator to the edge of the related key. Since such variation is therule rather than the exception, each key must be specially groundtoachieve a seating and a press fit in its milled pocket so as toprecisely position the perforaa tor by engagement with its flat.Normally, where the key must be held down, a precisely positioned tappedhole must be formed therein to receive a screw. Accordingly, the methodinherently dictates the need for a new key to be fit every time a toolmust be removed and replaced. Also difficulties basically reside inmilling a pocket for each key. Where a number of tools, such asperforators, are to be held in a single retainer, these problems arealso compounded. Machining obviously becomes more difficult andcriticalwhere the holes for locating perforators in a single retainerare in a close pattern. 1

In the double flat method of the prior art, the head of a tool, such asa perforator, requires the forming thereon of precisely parallel flats.There also must be precisely square grinding of related slots in thewall of the tool accommodating bore. Use of this method limits the toolarea in aretainer, an obvious disadvantage. Moreover, the flats mustinitially be formed with excess stock, since custom fitting is requiredin each applica tion of a perforator. This means it is impossible tostandardize procedures in application of perforators or any otherelement to a retainer using this method. Maintenance costs in usethereof will in any event be extremely high.

SUMMARY OF THE INVENTION The present invention substantially eliminatesthe basic problems and disadvantages of prior art practice in lockingelements such as perforating and forming tools and guide and die buttonsto their retainers, in a required position for use.

In accordance with the invention the element, a perforator for example,which is to be inserted in a bore of a retainer and fixed in a require-dposition for use, is formed with a flat on its head end. This flat,however, need not be held to a close tolerance. Used in conjunction withthe flatted portion of the perforator are two specially designed pins,which also have flats. In the area thereof to accommodate the flattedhead of the perforator, the bore wallis intersected by a pair ofcircularly spaced, axially directed, holes which are drilled and reamedin theretainer. These holes accommodate the aforementioned pins andwhere the bore wall is intersectedthereby, portions of the outer surfaceof the pins will project interiorly of the bore. When the perforator isinserted in its bore, the fiat on its head end is positionedapproximately parallel tothe holes which open to thebore, whereupon thepins may be inserted and rotatively adjusted to abut the flat on theperforator as it is adjusted to its required position of use. On

driving the pins into their holes the perforator is locked precisely inits required orientation and place. The pins are designed to facilitatetheir ready end positive application. i Y i The system and apparatus issuch that the perforators may be provided with. essentially standardizedflats while the inexpensive pins employed may be furnished in similarshape but in various sizes to meet a wide variety'of applications. Theconcept eliminates the need for a press fit tolerance between aperforator body and its bore to be closely held.

Of course the reference to a perforator is purely illustrative since theinvention is applicable to any element required to be similarly lockedto its retainer.

A primary object of the invention is to provide an. improved system andapparatus for keying and locking tool and die elements totheir retainerswhich is economicalto fabricate, more eflicieni. and satisfactory inuse, adaptable to a wide variety of applications and unlikely tomalfunction. i i

A further object of the invention 'is to provide improved means forkeying a cylindrical object to a retainer in a prescribed position ofuse.

Another object of the invention is to provide a system for keyingperforating and forming tools and their guides to their retainersfeaturing a novel pin as a key type positioning device. An additionalobject of the invention is to provide a novel pin type device usable tomore effectively key the head or body of a tool to its retainer whicheliminates the need for highly critical dimensioning and machiningprocedures in order to insure proper fit and position of the tool.

Another object of the invention is to eliminate the need for customforming and fitting of tool and die parts for their application to theirretainers.

A further object of the invention is to provide a simple means andsystem for standardizing tools and other elements which must be fixed inpredetermined positions for proper use thereof.

Another object of the invention is to provide systems and apparatus ofthe type described possessing the advantageous structural features, theinherent meritorious characteristics and the means and mode of useherein described.

With the above and other incidental objects in view as will more fullyappear in the specification, the invention intended to be protected byLetters Patent consists of the features of construction, the parts andcombinations thereof, and the mode of operation as hereinafter describedor illustrated in the accompanying drawings, or their equivalents.

Referring to the drawings wherein some but not necessarily the onlyforms of embodiment are shown,

FIG. 1 is a perspective fragmentary view of a die set embodying thesystem and apparatus of the invention;

'FIG. 2 is aside view of a new pin type keying device in accordance withthe present invention;

FIG. 3 is a perspective. view of the pin of FIG. 2;

FIG. 4 is an enlarged view of the head end of a perforator as keyed in aretainer per the illustration of FIG. 1; i

FIG. 5 is a view taken on line 5-5 of FIG. 4;

FIG. 6 shows a view similar to FIG: 5 illustrating the invention asapplied to headless die and guide inserts; and

FIG. 7 is a head end view of the structure of FIG. 6.

Like parts are indicated by similar characters of reference. throughoutthe several views.

Referring to the drawings FIG. 1 illustrates a die set in fragmentaryform to basically comprise a punch retainer plate 10, a base die plate12 and an intermediate stripper plate 14. As diagrammatically shown, theplate 10 mounts, in fixed relation thereto, a plurality of punch typeperforators l6 vertically aligned with guides 18 fixed in holes in thestripper plate 14 and die buttons fixed in accommodating holes in thedie plate 12.

In use the punch plate 10 will be fixed to the head of a reciprocableram providing thereon an upper die shoe (not shown) and die plate 12will be fixed to a base providing a lower die shoe'(not shown). Thestripperplate 14 will, of course, be resiliently suspended from thepunch plate 10 in a conventional manner. This provides the environmentof the present invention as here illustrated. As will be obvious, onlyso much of a die is here shown as may be necessary for an understandingof the present invention. 7

As illustrated, the punch type perforators 16 as well as the guides 18are each formed and locked in their retainers in accordance with thepresent invention. Since the concept is the same in each case, adescription of the keying and locking of a single perforatorshouldsuffice for an understanding of the present invention.

Each perforator shown in FIGS. 1-5 of the drawings is of the headedtype. This means that the head end of its body 16 is enlarged by aperipherally projected annular flange 22. The flange 22 is provided witha flat forator body. This flat need not be held to close tolerance.

For mount thereof the body of perforator 16 is inserted in a bore 26 ofthe plate 10. A counterbore 28 in the uppermost surface of the plate 10is designed to expand the upper end of bore 26 to nest the flange 22 atthe head end of the perforator body. A press fit tolerance between theperforator body 16 and the bore 26 need not be rigidly held.

The peripheral wall of the counterbored portion 28 of the bore 26 isintersected at one side thereof by two parallel slots which are closelyspaced. These slots are defined by two axially directed, relativelyclosely spaced holes 29, drilled perpendicular to the upper surface ofplate 10. The holes 29 are parallel to the bore 26 and may be drilledall the way through or partially through the plate. In any case thedepth of each is greater than that of flange 22 to receive a pin 30 asseen in the drawings. In cross-section, the pin 30 has the peripheralconfiguration of a circle interrupted at a chord thereof, the arcportion being formed on a uniform radius and having a' circumferentialextent which is g reaTF'tIianTSIYTThiS' 'e'rass aafifiuacmmsy taking acylindrical pin and machining a flat 36 on one side, to extend thelength of the pin. As seen in FIGS.- 2 and 3 the pin is comprised of alead section 34 which is relatively reduced in cross section relativethe remainder of the body thereof which is identified by the numeral 32.It is noted the flat 36 is ground at a slight taper, for example a .001inch taper, the length of the pin. This provides for the distance fromthe flat to the center of the pin to vary and to be the least at thelead end of the pin. This lends a capability to compensate for tolerancedifferences in the perforator and to set a rotational position thereofas will be further described. Where the hole 29 is a blind hole orcavity, the blind portion willhave an aperture for insertion of a toolto eject the contained pin as and when required.

In assembling the perforator, it isfirst dropped into its bore 26 so theflange 22 thereof seats to the shoulder formed therein by thecounterbore 28. It is r'otatively positioned so the flat 24 is generallyparallel to the plane defined by the holes or cavities (depending ontheir depth) 29. A pin 30, appropriately sized for the application isdropped in each hole 29, the introduction being facilitated by thereduction at the lead end thereof. The positions of holes 29 relativethe peripheral wall of counterbore 28 provides that the slots formedthereby will be wider than the flats 36 on' the pinsand a significantportion of the pins including the flats 36 will be presented in thecounterbored area. As will be seen in FIG. 4 the pins 30 as well as theperforator may be rotated to precisely position the perforatorreferenced to the related guide 18 and die button 20. With this positionestablished, in the case illustrated the flats '36 on the pins 30generally abut the flat 24, whereupon, they are driven in to lock theperforator in place, in its position of use. The pins may be driven tillthe heads are flush with the upper surface of plate 10 or deeper ifrequired to take up space between their flats and the flat 24.

In accordance with the invention pins may be provided in various sizes,with various width flats and with a variable spacing of the flat fromthe center of the pin. This means that no holeor bore tolerance need beclosely held and pins may be selectively applied to precisely suit theapplication and to insure a precise position of the flat 24 on theperforator as it is locked in place. It is to be understood, however,that by reason of the form of the pins, they have a significant range toaccommodate variation in fit of the perforator andthey themselves can besimply rotated if required to establish that a portion thereof will havean insured bearing contact with the flat 24 in its required position.The optimal position will however be as illustrated with flats 36 and 24flush abutted and can be normally achieved with reasonable variation inestablished tolerances which in any event need not be critically held.Attention is directed to the fact that the pins 30 are securelycontained in the holes 29, which insures a firm and seated backing andretention thereof in use.

The important benefits of the key-lock system of the invention should beself-evident. The locations of holes 29 provides a web therebetweengiving a multiple reinforcement to the key structure within the retainerplate. It also permits the perforator to be removed without necessarilyremoving pins 30, if such is desired. By tape control, a set relationofthe two holes 29 andthe perforator bore may be early established in thefirst instance. This produces, very simply, critical control points andenables that holes or bores used merely be drilled and reamed.Tolerances can be 0.0002 inch and even somewhat greater. For'example'there can be a 10.0005 inch' spread from the centerline of theperforator and between the two pins. This dictates economy V in use ofthe system and enables that the components used therein may bestandardized andmade shelf type items. I

An important result of the system and apparatus of the invention is thereliability and repeatability of alignment, within 0.0001 inch and0.0002 inch in width of the' flat on the perforator component. This iswell within the tolerances required for efficient reassembly duringmaintenance procedures. While the invention has been described inreference to placement and lock of a perforator, obviously the conceptis equally applicable to any element required to be locked to andprecisely positioned in a retainer.

FIGS. 6'and 7 of the drawings illustrate the manner of its applicationto a headless element, such as a headless perforator. In this case thehead end of the perforator 16 (which has no flange) is cut back toproduce a flat 24 thereon which inset from its outer periphery.

This flat positions uppermost as the perforator is inserted in a bore26' of the plate corresponding to' plate 10. At its uppermost end, andto one side thereof thebo're 26' is expanded by an arcuate cut, in thewall thereof, the depth of flat .24'. This produces an offset arcuatewall segment 43 formed on a radius smaller than that of bore 26' theends of which connect to the wall of the bore by short offset wallsegments 45 formed by small holes41 drilled in the upper surface ofplate 10'. The purpose of this will soon be obvious.

In this case the holes 29 (corresponding to previous holes 29) aredrilled in the upper surface of retainer plate 10' to form parallelslots opening to the bore in theareabetween adjacent extremities. ofwall segments 43 and 45. I

As the perforator l6' is inserted in bore 26, it is ro tated so its flat24' is caused to face the plane defined by the holes 29'. The pins 30corresponding to pins 30, as previously described, are inserted inholes. 29' to fix said element in place by a have flatted portions 36thereofv face the flat 24, whereupon a flat key 44 is appliedtherebetween. In this case the key 44 projects the surface of flat 24'and the pins 30 make spaced contact therewith in a manner as previouslydescribed with reference to flat 24.

The expansion of the bore 26 in the upper end thereof is sufficient, asseen in FIG. 7, to accommodate the ends of key 44 in offsets provided inthe bore wall by the wall segments 45, with sufficient clearance topermit rotation of the perforator and its flat for precise positioningthereof. Moreover, the pins 30 may be selectively applied, in a size tosuit the application, and rotated in their holes to make bearing'contactwith the key 44 to fix the same and the perforator in place. The

key acts as a wedge as it and the pins are simulta 'neously driven intoplate 10. The perforator is simply and precisely locked in placethereby.

Substantially all the advantages previously described are availablein-use of the invention in reference to contributes to the primaryobjective of standardization of parts for various application. 7 I I IFrom the above description it will be apparent that there is, thusprovided adevice of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions, de-.tail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages. l l

' While in order to comply with the statute the invention has beendescribed in language. more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures showmbut thatthe means and construction herein disclosedcomprise but one of several modes of putting the invention into effectand the invention .is therefore claimed in any of its forms ormodifications within the legitimateand valid scope of the appendedclaims.

I claim:

1. Apparatus for locking an element in arequired po- .sition of use,within a bore or recess of a retainer, characterized by a flat formed onone side portion :of said element which disposes in saidbor e or recess,said retainer having aplurality of holes or cavities therein opening tothe said bore or recess in the area of said flat and means received ineach said hole or'cavity at least 1 a portion of which projects insaidzbore or recess to' abut said flat, the projected portions of saidmeans in said holes or cavities providing'for selective and pluralengagement of said flat at relatively spaced surface portions thereof toprecisely position said flat and said element thereby in a requiredposition of use and said means within said holes or cavities providingmeans to locking engagement thereof to said flat.

2. Apparatus as in claim 1 characterized by said holes beingaxiallydirected in a generally parallel orientation and saidmeansreceived therein having a pin-like form.

3. Apparatus as in claim 2 characterized by there being two said holesthe axes of which are generally parallel to the axis of said bore orrecess, said means of pin-like form including surface portions whichproject laterally into said bore or recess, and by rotative positionthereof are adapted to engage selected portions of the flat on saidelement to orient and fix the same in place.

4. Apparatus as in claim 3 wherein said means of pinlike form having alongitudinally tapered surface portion facilitating the introductionthereof in said holes and the cross section thereof being determinativeof the extent said surface portions project laterally into said bore orrecess.

5. Apparatus as in claim 4 wherein said means of pinlike form includeflatted surface portions which may be presented interiorly of said boreor recess to abut relatively spaced surface portions of said flat.

6. Die apparatus as in claim 1 wherein said element is a die tool thehead end of which has an external flange seating in a complementarilyexpanded portion of said bore or recess, said flat being provided onsaid flange and said means received in each said hole or cavity havingflatted portions positioning said tool by interrelation with the flat onsaid flange 7. Apparatus for locking an element in a required positionof use, within a bore or recess of a retainer, a portion of said elementdisposing within said bore or recess, characterized by said retainerhaving a plurality of holes or cavities portions of which are open tosaid bore or recess and means disposing partially in said bore or recessand in said holes or cavities arranged to effect a position and lock ofsaid element to said retainer in a required position of use, said meansincluding a pair of pins the positions of which are determinative of thefixed position of said element.

8. Apparatus as in claim 7 wherein said holes or cavities comprise apair of laterally spaced holes or cavities and said pins disposepartially therein and partially in said bore or recess to position andfix said element by direct engagement with spaced portions thereof.

9.-Apparatus as in claim 7 wherein a side portion of said elementincludes a flatt'ed portion, said pins are non-circular in cross sectionand said element and pins are rotatable to establish a required relationtherebetween to determine the desired fixed position of said element. I

10. Apparatus as in claim 9 wherein a plate-like insert is interposedbetween said pins and said flatted portion of said element to lock saidelement in its re-.

tainer.

11. Apparatus as in claim 7 wherein said pins have a generally parallelspaced relation and a non circular cross section in respect to at leastthose portions thereof partially in said holes or cavities and partiallyin said bore or recess and the rotation thereof providing spaced pointswithin said recess or cavity which determine the required position ofsaid element with respect to said retainer. a

12. Die apparatus as in'claim 7 wherein said element is an operativeinsert in a tool or die plate and said fiat is formed thereon and saidpins including flatted portions functionally related to said flat tocontrol the rotative position thereof in said bore or recess in saidretainer.

1. Apparatus for locking an element in a required position of use,within a bore or recess of a retainer, characterized by a flat formed onone side portion of said element which disposes in said bore or recess,said retainer having a plurality of holes or cavities therein opening tothe said bore or recess in the area of said flat and means received ineach said hole or cavity at least a portion of which projects in saidbore or recess to abut said flat, the projected portions of said meansin said holes or cavities providing for selective and plural engagementof said flat at relatively spaced surface portions thereof to preciselyposition said flat and said element thereby in a required position ofuse and said means within said holes or cavities providing means to fixsaid element in place by a locking engagement thereof to said flat. 2.Apparatus as in claim 1 characterized by said holes being axiallydirected in a generally parallel orientation and said means receivedtherein having a pin-like form.
 3. Apparatus as in claim 2 characterizedby there being two said holes the axes of which are generally parallelto the axis of said bore or recess, said means of pin-like formincluding surface portions which project laterally into said bore orrecess, and by rotative position thereof are adapted to engage selectedportions of the flat on said element to orient and fix the same inplace.
 4. Apparatus as in claim 3 wherein said means of pin-like formhaving a longitudinally tapered surface portion facilitating theintroduction thereof in said holes and the cross section thereof beingdeterminative of the extent said surface portions project laterally intosaid bore or recess.
 5. Apparatus as in claim 4 wherein said means ofpin-like form include flatted surface portions which may be presentedinteriorly of said bore or recess to abut relatively spaced surfaceportions of said flat.
 6. Die apparatus as in claim 1 wherein saidelement is a die tool the head end of which has an external flangeseating in a complementarily expanded portion of said bore or recess,said flat being provided on said flange and said means received in eachsaid hole or cavity having flatted portions positioning said tool byinter-relation with the flat on said flange.
 7. Apparatus for locking anelement in a required posItion of use, within a bore or recess of aretainer, a portion of said element disposing within said bore orrecess, characterized by said retainer having a plurality of holes orcavities portions of which are open to said bore or recess and meansdisposing partially in said bore or recess and in said holes or cavitiesarranged to effect a position and lock of said element to said retainerin a required position of use, said means including a pair of pins thepositions of which are determinative of the fixed position of saidelement.
 8. Apparatus as in claim 7 wherein said holes or cavitiescomprise a pair of laterally spaced holes or cavities and said pinsdispose partially therein and partially in said bore or recess toposition and fix said element by direct engagement with spaced portionsthereof.
 9. Apparatus as in claim 7 wherein a side portion of saidelement includes a flatted portion, said pins are non-circular in crosssection and said element and pins are rotatable to establish a requiredrelation therebetween to determine the desired fixed position of saidelement.
 10. Apparatus as in claim 9 wherein a plate-like insert isinterposed between said pins and said flatted portion of said element tolock said element in its retainer.
 11. Apparatus as in claim 7 whereinsaid pins have a generally parallel spaced relation and a non circularcross section in respect to at least those portions thereof partially insaid holes or cavities and partially in said bore or recess and therotation thereof providing spaced points within said recess or cavitywhich determine the required position of said element with respect tosaid retainer.
 12. Die apparatus as in claim 7 wherein said element isan operative insert in a tool or die plate and said flat is formedthereon and said pins including flatted portions functionally related tosaid flat to control the rotative position thereof in said bore orrecess in said retainer.